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<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="container.known_issues"></a><a class="link" href="known_issues.html" title="Known Issues">Known Issues</a>
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<div class="toc"><dl class="toc"><dt><span class="section"><a href="known_issues.html#container.known_issues.move_emulation_limitations">Move
      emulation limitations in C++03 compilers</a></span></dt></dl></div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="container.known_issues.move_emulation_limitations"></a><a class="link" href="known_issues.html#container.known_issues.move_emulation_limitations" title="Move emulation limitations in C++03 compilers">Move
      emulation limitations in C++03 compilers</a>
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<p>
        <span class="bold"><strong>Boost.Container</strong></span> uses <span class="bold"><strong>Boost.Move</strong></span>
        to implement move semantics both in C++03 and C++11 compilers. However, as
        explained in <a href="http://www.boost.org/doc/libs/release/doc/html/move/emulation_limitations.html" target="_top">Emulation
        limitations</a>, there are some limitations in C++03 compilers that might
        surprise <span class="bold"><strong>Boost.Container</strong></span> users.
      </p>
<p>
        The most noticeable problem is when <span class="bold"><strong>Boost.Container</strong></span>
        containers are placed in a struct with a compiler-generated assignment operator:
      </p>
<pre class="programlisting"><span class="keyword">class</span> <span class="identifier">holder</span>
<span class="special">{</span>
   <span class="identifier">boost</span><span class="special">::</span><span class="identifier">container</span><span class="special">::</span><span class="identifier">vector</span><span class="special">&lt;</span><span class="identifier">MyType</span><span class="special">&gt;</span> <span class="identifier">vect</span><span class="special">;</span>
<span class="special">};</span>

<span class="keyword">void</span> <span class="identifier">func</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">holder</span><span class="special">&amp;</span> <span class="identifier">h</span><span class="special">)</span>
<span class="special">{</span>
   <span class="identifier">holder</span> <span class="identifier">copy_h</span><span class="special">(</span><span class="identifier">h</span><span class="special">);</span> <span class="comment">//&lt;--- ERROR: can't convert 'const holder&amp;' to 'holder&amp;'</span>
   <span class="comment">//Compiler-generated copy constructor is non-const:</span>
   <span class="comment">// holder&amp; operator(holder &amp;)</span>
   <span class="comment">//!!!</span>
<span class="special">}</span>
</pre>
<p>
        This limitation forces the user to define a const version of the copy assignment,
        in all classes holding containers, which might be annoying in some cases.
      </p>
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<div class="copyright-footer">Copyright © 2009-2018 Ion Gaztanaga<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
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